Electric fixture



April 8, 1941. G. ARRAS ELECTRIC FIXTURE Filed Aug. 26, 1939 n l d Q u I J km /I WV W///A w fo w 7 ATTORNEY.

Patented Apr. 8, 1941 `UNITED STATES PATENT OFFICE ELECTRIC FIXTURE George Arras, Chicago, Ill.

Application August ,26, 1939, Serial No. 292,053

1l Claims.

This invention relates in general to a connection for iixtures which locks parts together by a relative rotation thereof and has more particular reference to an electric iixture in which supporting and electrical connections are made by the relative rotation of `a fixed ceiling, wall or plug outlet and a rotatable socket supported thereby and preferably connected to a reflector or a similar enclosing casing.

An important object of the invention is in the provision of interlocking rotatable parts carried by the plug and socket members and interengaged by relativeI movement of the parts to lock them together against accidental removal or disconnection.

A further object of the invention is inthe provision of springpressed electrical `connectors carried by the plug and socket parts which are maintained in sliding contact during the interengagement of the parts, together with locking means for maintaining the interengaging parts in limiting positions depending upon the rotation thereof.

Other and further objects of the invention will appear hereinafter, the accompanying drawing illustrating the preferred embodiment of the invention in which Fig. 1 is a longitudinal sectional view of an electric nxture connection including a portion of a shade or reflector;

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1; l

Fig. 3 is a View looking at the open or inner end of the plug member;

Fig. 4 is an end view of the socket member which cooperates with the open end of the plug as shown in Fig. 3; and

Fig. 5 is a perspective of the inner locking and interengaging parts of the plug and socket members which secure them together upon the relative rotation thereof.

In electric iixture connections it is desirable to provide not only an interlocking mechanical con nection but also a spring-pressed: electrical connection, both of which are locked against separation when they are connected by a relative movement which requires the compression of a spring as well as a limited rotary movement to move the interengaged parts from locking to unlocking position.

In the present invention the parts are connected by inserting the movable member within the fixed member to overcome the tension of springs therein making the electric connection, and then the movable member is rotated a portion of a turn and the inward pressure released, which causes an interlocking of the parts in connected position from which they cannot be disengaged without rlrst compressing the spring and then rotating the movable member in a reverse direction. No threading movement of one part into the other is necessary but only a limited rotation of the movable member of perhaps 1A; or 1A; of a turn in order to effect the connection or disconnection of the parts. l

Referring now more particularly to the drawing,` a iixed outlet for a wall, ceiling, or even suspended by a conduit pipe Ill, comprises a casing I I in which is seated an insulating terminal ,block I2 pressed outwardly from the bottom bysprings i3. Through a central opening I4 conductors I5 extend through the pipe I0 and are connected to terminal screws I5 and II. These screws extend through clamping plates IB and IS respectively for engaging arcuate contact blades 20 and 2| of difieren-t curvature, the extremities of which extend over opposite raised ribs 22 and are separated by ribs 23 between adjacent sectionsso that electrical connections can be made at different distances from the center with either ofthe two sets of contacts without danger of a short-circuit between them. The clamping plates I8 and I9 are held in place from the inner or under side oi the terminal block I2 by fastening screws 2,4 which draw them tightly against their respective Contact blades 20 and 2|, holding them tightly in place and providing terminals for attaching `the electrical conductors I5 by means of the screws it and n.

The terminal block preferably has recesses 25 corresponding with recesses 26 in the wall of the casing il to provide seats for the springs I3 which abut the bottom of the casing at one end and the bottom of the recess 25 at the other end.

In one edge of the block I2 is a notch 2'I en gaged by a tongue or projection 2B `at the inner edge of the casing tI which prevents rotation of the block in the casing and limits its movement to a vertical direction therein, thus preventing the conductors I5 from being twisted and torn loose by any movement of the insulating block.

To limit the outward movement of the block in the casing due to the action of springs I3, a ro.. tatable retaining ring 3i? is seated against an enlarged shouldered portion 3l in the casing `II which has a cenrtal opening 32 through which the inner edge 33 of the block i2 extends. The ring is substantially right angled in cross section to provide an upright iiange 34 having a number of recesses 35 spaced about an opening inwardly from the periphery to the bottom wall of the ring so that fastening screws 36 inserted through the wall of the casing will engage over theA `base of the ring and hold it in place against `outward movement due to its engagement with `the springpressed insulating block I2. Each of .the 'ange openings 35 inthe retaining ring is of suicient length along the base to permit a limited rotative movement of the ring within `the casing and at the inner edge of the ring are notches or rew cesses 31 and 3! for seating a projection 39 at the outer edge of the insulating block I2 so that when the ring 3D is rotated from one limiting position to another the block l2 must first be pressed out of engagement with the ring but in either limiting position of the ring it will engage the projection 39 of the block in one of the openings 31 0r 38.

In the movable member of the connection an insulating block or plug 40 has a recess 4| at one end for receiving a lamp socket 42 secured at opposite edges by fastening screws 43 extending through the block to the inner end thereof where they are connected to a circular contact ring 44 of a diameter to engage the outer contact ngers of the insulating block l2. Also located centrally in the socket shell 42 is a spring contact 45 connected through the plug by a fastening screw 45 with a central contact disc 41 at the inner end of the plug adapted to make connection with the Contact block connections 2|. Below the level of the plug contacts 45 and 41 is a circular shoulder 43 upon which is seated iirst the inwardly turned end 49 of a shade or reflector shell 59, then a oating ring 5| having outer projections 52, and then an operating ring 53 with upwardly projecting teeth or lugs 54, the ring and the extremity of the reector shell being clamped tightly in place with a washer 55 therebetween by fastening screws 55 inserted from the inner side of the socket opening 4| of the plug.

The washer 55 is slightly greater in thickness than the floating connector ring 5| so that the ring has a loose sliding t permitting it to be rotated freely in either direction. This connector ring may be slightly distorted so that it will frictionally engage but will rotate freely when engaged and will not spin idly between its confining parts.

At the inner edge of the casing opening coinciding with the location of the screws 36 are grooves 51 located to receive the projections 52 of the connector ring 5| and permitting the socket member 40 to be inserted within the casing member -until the projections 52 of the connector ring engage the studs or screws 35 or an angular projection 59 at one end of the recess 35. Extending outwardly from the retaining ring at one side of one or both of the recesses 31 and 38 are lugs 58 located in the path of the teeth 54 so that if the lugs 58 engage on top of the teeth 54 when the connecting parts are inserted together a slight adjusting movement of the connector ring 5| with respect to its operating ring 53 is necessary in order that the lug 58 will engage between two of the teeth. At this time the electrical connections of the plug and socket members are brought into engagement and electrical Contact, the plug member must be inserted against the pressure of the springs I3 and the parts of the connector are then given a rotative movement about equal to the length of the opening or to move the retaining ring from a position Where the recess 31 is engaged by the lug 39 to its other limiting position where the lug engages the recess 33.

In one limiting position of the retaining ring 39 the angular projections 59 abut the screws 36 and thereby position one edge 60 of each opening 35 in alignment with one edge of the groove 51. In this position the plug member is inserted within the receiving housing, the projections 52 passing freely through the entrance of the opening 35 until the projections 52 of the connector ring tween the teeth 54 of the operating ring 53 theA retaining ring is rotated with respect to the lugs of the floating connector ring 5|, the outer ends of which are seated in the grooves 51 and the intermediate portions of these lugs are seated in an undercut portion 6| of the recess 35 forming an outer projection 62 having a locking tip 63 at each recess. When the inward pressure against the springs |3 is then released the projections 52 will be forced outwardly by the springs into the undercut portions 6| of each recess 35 where they are prevented from opposite or disengaging rotary movement by the tips 63.

In order to disengage this locking connection the socket member must be pressed inwardly against the tension of the springs |3 until the projections 52 of the oating connector ring are within or free from the locking tips 63 when the parts may be rotated reversely, returning the parts to the registering position from which they may be separated or removed.

When the parts are locked together it will be seen that the connector ring 5| is seated in the grooves 51 of the casing member and the retaining rings is rotated over the projections and resiliently locked and seated in the undercut portion by means of the springs of the insulating member I2. At all times after the electrical conductors of the members are moved together by the insertion of one part within the other, the electrical connection is maintained because the springs I3 hold the insulating member |2 and its electrical connectors tightly against those of the member 45, the connections and engagement between the parts requiring only a limited rotative movement between the conductors and between the parts to effect the connection and disconnection thereof. The shade or reector being tightly secured to the socket member 4D is also held against rotation and cannot be rotated or moved outwardly without rst pressing the connected members together against the springs |3 and then rotating the parts as previously described. Thus the connected parts are locked tightly in engagement against rotative movement until they are manually released.

While this structure is described in connection with an electric xture having electrical conductors also engaged and connected thereby, the members may be connected and retained in nonrotative engagement by similar connecting parts in which the insulating members I2 and 40 simply engage and do not have electrical connections thereon.

I claim:

1. A xture connection comprising relatively movable parts, one insertable in the other, a locking ring with edge recesses movable in one part, a locking plate having projections to engage in the recesses rotatable on the other part, and means on one Part interengaged with means on the second part by the insertion and movement of one part in the other for interlocking the plate and the ring.

2. A xture connection comprisinGr relatively rotatable parts, one insertable in the other, a locking ring with edge recesses movable in one part, grooves in said part corresponding with the recesses of the locking ring, a locking plate on the other part having projections to engage in the recesses and grooves, and means on one part inter-engaged with corresponding means on the other part by the insertion and rotation of o-ne part inserted in the other for rotating the locking ring with respect to the plate having its projections seated in the grooves for interlocking the parts.

3. A fixture connection comprising relatively rotatable parts, one insertable in the other, a locking ring with undercut recesses at the edge movable in one part, grooves in the inner edge of the locking ring part corresponding to the edge openings of the locking ring, a locking plate on the other part having projections insertable through the edge recesses and engaging in the grooves, and means on one part inter-engaged with means on the second part by the insertion and movement of one part in the other for moving the locking ring so that the undercut recesses thereof overlap the projections of the locking plate holding the parts together.

4. A fixture connection in accordance With claim 3, comprising an intermediate springpressed member seated in the part containing the locking ring, having an outer projection and the ring having openings for engaging the projection and thereby yieldingly limiting the movement of the ring in both directions.

5. A fixture connection comprising relatively rotatable parts, one insertable in the other, a` locking ring with edge recesses having undercut projections movable in one part, spring-pressed means Within the part engaging the ring for limiting its movement in both directions, grooves at the inner edge of the locking ring part corresponding to the openings of said recesses, a locking plate movable on the other part having projections to engage in the recesses and grooves, means carried by said other part for engaging the locking ring and moving it relatively to the locking plate engaged in said grooves and against the pressure of said resilient means to interlock the ring and the plate, holding the rotatable parts together.

6. A fixture connection comprising relatively rotatable parts, one insertable in the other, a locking ring movable in one part having a rim with edge openings and undercut recesses extending irom the openings, inside grooves in said locking ring part corresponding to the edge openings, a locking plate on the other part having projections to engage in the recesses and grooves, resilient means Within the first part engaged by the insertion of the other part and depressed by the insertion of the locking plate projections, means on the locking plate part to rotate the locking ring when the resilient means is so depressed, interengaging the projections seated in said grooves, and said resilient means holding the projections in the undercut recess portions locking the parts together and preventing their relative movement in either direction.

'7. A fixture connection comprising relatively rotatable parts insertable one Within the other, interengaging means carried by each of the parts including undercut marginal recesses in one of the parts and projections on the other part, said means on one part being inter-engaged with means on the second part by inserting and turning one Within the other, and spring-pressed means carried by one of the parts engaged and depressed by the other part in moving the -projections into the undercut portions of the recess, the projections being held by the resilient means in the undercut portions for locking the parts together and preventing their rotational movement in either direction until the said resilient means is rst depressed.

8. A connection of the class described, compricing relatively rotatable parts, one having a movable locking ring with a flanged edge and spaced, openings from the iianged edge to an undercut recess, a locking plate rotatable on the other part held in place by an operating member having projections adapted to engage the locking ring for turning it, the locking plate having projections and. the opposite part having means for engaging the extremities of the projections when they are seated in the openings of the locking ring, the locking ring being rotatable by the operating member to engage the projections of the locking ring in the undercut portion of the recesses, and resilient means opposing the insertion of one member in the other for holding the projections against the stops of the locking ring and preventing relative rotation of the parts unless said resilient means is first compressed.

9. An electric xture connection comprising relatively rotatable parts, one insertable in the other, electrical contact members carried by the parts and engaged when they are inserted one within the other, a movable interlocking connectio-n between the parts separate from the electrical contact members comprising a locking ring having recesses and a locking plate having projections engaging the recesses and relatively movable on the .diierent parts when they are inserted one Within the other and turned a limited amount in one direction, and resilient means engaging one part carrying the electrical contact means and tending to press it outwardly so that the contacting means of the other part must be pressed inwardly to overcome the resilient means before the interlocking connection can be made or disconnected.

10. An electrical fixture connection in accordance with claim 9 in which the electrical contact members comprise .an insulating member carried by one of the parts having arcuate contact ngers, an insulating member carried by the other part having projecting and separated electrical contact members to engage the said iingers, the said contacting members and ngers being separate from and engaged before the interlocking engagement of the parts and maintaining the electrical connection during the interlocking and releasing of the interlocking engagement.

11. In an electric xture connection, a housing part having an electric terminal block resiliently mounted therein and nxed against rotation, a relatively rotatable part insertable in the housing having a projecting insulating part with contacts therein to engage the contacts of the terminal block in the housing and rotatable in engagement with the contact Without disengagement therefrom, and an interlocking connection between' the housing and insertable parts comprising a ring rotatably mounted in the housing and engagedby the resilient terminal block, the locking ring having undercut recesses at its edges and the rotatable part having a relatively rotatable plate with projections for engaging the recesses of the locking ring, and an operating ring member for holding the plate in position, the operating ring having projections for engaging the locking ring so that the locking ring can be rotated to engage over the projections of the locking plate when the resilient block in the housing isi pressed out of engagement with the locking r ng.

GEORGE ARRAS. 

